Panorama Quality

[With The Birds]

Yep, we can sit here and jibber jabish all day long

Here’s what I get when I shoot a pano in manual.

View attachment 94265

View attachment 94266 View attachment 94267

You can see the stitch line in every one of these. You can see the line because the exposure is off where they come together. This is pretty obvious in the second pano. These panos are also edited with the shadows and highlights at their max. They also all have a radius gradiant filter added too, bringing down the exposure, in the sky, over 2 points! If not, I get a blown out sky and ground that’s too dark to see anything. If these were shot in auto, the sky wouldn’t be so bright and the ground wouldn’t be so dark.

I wish someone could post some 360 panos shot in auto.....

Excellent examples for the discussion.

Image one demonstrates that the stitching algorithms, as good as they are, have revealed their limitations. You may have got a better result assigning manual control points in ptgui. Auto alignment is problematic unless you can physically set the nodal point of the lens to be constant for all camera orientations employed when acquiring the source images.

Both images show a wide variance in brigthess throughout the image. As expected. Simply because you have captured such a wide scene and compressed it into a single frame.

 

[With The Birds]

Jumping in on this thread. As far as I know, if you are in manual and leave your settings locked and take multiple pics across the landscape to make a pano, then the EV will change if there is more or less light in the various pictures you take. Let’s say you take your exposure reading with the camera framed where The Sun is not in the frame and you lock your settings, then when you pan over and take a shot where The Sun is in the frame then the EV measured will be higher. More light coming in but you haven’t changed any settings to compensate. Auto will remeter for each shot and will by definition try to keep the EV at zero.

When I do panos with my DSLR I’ve always used manual and exposed for the part of the scene that is most important and don’t change settings. Why do I do this? As alluded to earlier, if you shoot in auto then the settings will change on you to compensate for brighter parts of the sky. This may sound like a good thing. But sometimes it’s not when pictures taken with different settings are stitched. When one picture is forced to expose darker than the one next to it, you can end up with unnatural transitions across the sky.

If you had a camera that could take one wide pano image with one press of the shutter you only get one meter reading - one set of settings. Shooting many based one one exposure measurement and set of settings, in essence, accomplishes the same thing.

I suppose in theory one could say, “but exposing for each shot let’s you get more dynamic range by dropping highlights and lifting shadows in the different frames.” But AFAIU this has been discouraged because of trouble caused to the stitching process. But maybe stitching algorithms are getting better to allow it.

What changes (or should I say almost always changes in practice) is the amount of light entering the lens for different camera orientations. The EV remains constant, EV is simply the combination of AV (aperture) and TV (shutter duration) which is a handy reference for this who like to do things manually. In earlier times pre light meters, it was a necessity to understand the relationship. Below is an EV table for 100ASA and outdoor shooting in sunlight. Remember the sunny 16 rule? Shutter speed = 1/ISO at f16.

As can be seen for any charge of EV TV and or AV must be altered accordingly. An EV reading of -1 simply mean aperture is closed or TV increased by one stop. It’s a meaningful reference.

 

[With The Birds]

Excellent examples for the discussion.

Image one demonstrates that the stitching algorithms, as good as they are, have revealed their limitations. You may have got a better result assigning manual control points in ptgui. Auto alignment is problematic unless you can physically set the nodal point of the lens to be constant for all camera orientations employed when acquiring the source images.

Both images show a wide variance in brigthess throughout the image. As expected. Simply because you have captured such a wide scene and compressed it into a single frame.

Shooting all frames for the pano at fixed EV (locked AV and TV) will give you the most accurate representation of the variations in brightness levels in the scene, it must as it is the same as shooting a single frame with a lens with wider FOV. In shooting this image I metered for the brightest area and proceeded to take all frames at those settings.

 

[bsartist]

What changes (or should I say almost always changes in practice) is the amount of light entering the lens for different camera orientations. The EV remains constant, EV is simply the combination of AV (aperture) and TV (shutter duration) which is a handy reference for this who like to do things manually. In earlier times pre light meters, it was a necessity to understand the relationship. Below is an EV table for 100ASA and outdoor shooting in sunlight. Remember the sunny 16 rule? Shutter speed = 1/ISO at f16.

View attachment 94271

As can be seen for any charge of EV TV and or AV must be altered accordingly. An EV reading of -1 simply mean aperture is closed or TV increased by one stop. It’s a meaningful reference.

Oh man. With the Birds totally schooled me. It’s definiteky a terminology issue and I was wrong as I believe helihover was since I think we were working from the same incorrect definition of EV. I never got in the habit of thinking in terms of EV when doing my still photography so I got sucked into thinking of it as photometric exposure. When I looked up on Wikipedia I found this sentence which I think encapsulates the essence of the initial misunderstand which started before I jumped in and started jabbering:

"Exposure value" indicates combinations of camera settings rather than the luminous exposure (aka photometric exposure)

 

[With The Birds]

Oh man. With the Birds totally schooled me. It’s definiteky a terminology issue and I was wrong as I believe helihover was since I think we were working from the same incorrect definition of EV. I never got in the habit of thinking in terms of EV when doing my still photography so I got sucked into thinking of it as photometric exposure. When I looked up on Wikipedia I found this sentence which I think encapsulates the essence of the initial misunderstand which started before I jumped in and started jabbering:

"Exposure value" indicates combinations of camera settings rather than the luminous exposure (aka photometric exposure)

Yep. The value of light intensity over a given area is expressed as Ev (little v which I can’t find on the iPhone keyboard) which we would use to demonstrate any change in EV.

 

[bsartist]

Shooting all frames for the pano at fixed EV (locked AV and TV) will give you the most accurate representation of the variations in brightness levels in the scene, it must as it is the same as shooting a single frame with a lens with wider FOV. In shooting this image I metered for the brightest area and proceeded to take all frames at those settings.

View attachment 94272

I agree and I think I mentioned that point about comparing it to a single frame with one exposure. However I’m willing to consider the ability to improve dynamic range by taking different exposures for different parts of the resulting pano. It’s kind of like what our eye does. In other words, maybe improve on the single exposure FOV scenario. But the stitching has to handle it.

 

[With The Birds]

I agree and I think I mentioned that point about comparing it to a single frame with one exposure. However I’m willing to consider the ability to improve dynamic range by taking different exposures for different parts of the resulting pano. It’s kind of like what our eye does. In other words, maybe improve on the single exposure FOV scenario. But the stitching has to handle it.

What I tend to do where the dynamic range if the sensor is likely to be exceeded is shoot two pano’s- one metered for the sky (exposed to the right of the histogram) and one to give me good tonal range in the foreground). I can then blend the images as layers in photoshop to retain a sense of the scene lighting while preserving detail and overcoming the limitations of the camera to handle the full luminance contrast. You can also acquire 3 or more frames for each shot (at say +/- 3 EV) and tonemap before stitching. Things tend to look off when shooting source images at average weighted exposure settings IMO.

 

[bsartist]

What I tend to do where the dynamic range if the sensor is likely to be exceeded is shoot two pano’s- one metered for the sky (exposed to the right of the histogram) and one to give me good tonal range in the foreground). I can then blend the images as layers in photoshop to retain a sense of the scene lighting while preserving detail and overcoming the limitations of the camera to handle the full luminance contrast. You can also acquire 3 or more frames for each shot (at say +/- 3 EV) and tonemap before stitching. Things tend to look off when shooting source images at average weighted exposure settings IMO.

Great idea. I’ll have to mess with that. I haven’t run into such extremes yet. But that’s a great technique to try. Kind of like an HDR pano

 

[With The Birds]

Great idea. I’ll have to mess with that. I haven’t run into such extremes yet. But that’s a great technique to try. Kind of like an HDR pano

While not a fantastic example, this PANO is stitched from pre-processed HDR images. The defect in this image is obvious, I metered from the centre and shot three frame sets at +/- 2EV. Clearly I needed more than 2EV from my metered exposure to avoid the highlights blowing out in the brightest region of the sky.

 

[bsartist]

While not a fantastic example, this PANO is stitched from pre-processed HDR images. The defect in this image is obvious, I metered from the centre and shot three frame sets at +/- 2EV. Clearly I needed more than 2EV from my metered exposure to avoid the highlights blowing out in the brightest region of the sky.

View attachment 94277

IMHO blowing out that small portion of the sky doesn’t ruin the pic. At least the water below retains its highlight detail.

 

[With The Birds]

IMHO blowing out that small portion of the sky doesn’t ruin the pic. At least the water below retains its highlight detail.

A good observation probably is that the stitching lines aren’t obvious. PT GUI does a great job of averaging and blending for varying brightness between frames. Another advantage of stitching with PT GUI is that you can assign manual control points (I had to do that here) and even mask areas of overlapping images giving you a great chance of avoiding artifacts. Working manually @Helihover would would likely be able to eliminate the issues he is experiencing. By manually I mean acquiring the images with at least 40% overlap and stitching in PtGUI or another app that allows user control of output.

 

[Helihover]

What changes (or should I say almost always changes in practice) is the amount of light entering the lens for different camera orientations. The EV remains constant, EV is simply the combination of AV (aperture) and TV (shutter duration) which is a handy reference for this who like to do things manually. In earlier times pre light meters, it was a necessity to understand the relationship. Below is an EV table for 100ASA and outdoor shooting in sunlight. Remember the sunny 16 rule? Shutter speed = 1/ISO at f16.

View attachment 94271

As can be seen for any charge of EV TV and or AV must be altered accordingly. An EV reading of -1 simply mean aperture is closed or TV increased by one stop. It’s a meaningful reference.

I figured we were talking about something different. So the EV value displayed on the app (which is what I was talking about) is not really EV? The displayed EV on my Nikon works the same way.

 

[With The Birds]

I figured we were talking about something different. So the EV value displayed on the app (which is what I was talking about) is not really EV? The displayed EV on my Nikon works the same way.

Seemingly we are past the accusations of not understanding, being argumentative etc- awesome!

The number depicted as the value for EV is simply the difference between the exposure that will result using the current settings for TV, AV & ISO and what the camera light metering has determined to be the required exposure. The fact the number changes when you move the camera between areas of changing brightness in itself proves EV hasn’t changed, it’s when it remains at 0 we know that there has been a change to TV, AV or ISO.

I’m almost sorry I raised this originally however my intent was only to assist you with your original question.

If you haven’t yet I would suggest you have a play with PTGUI- you will get last a lot of the issues you are having. It’s fiddly but it works.

 

[bsartist]

The number depicted as the value for EV is simply the difference between the exposure that will result using the current settings for TV, AV & ISO and what the camera light metering has determined to be the required exposure. The fact the number changes when you move the camera between areas of changing brightness in itself proves EV hasn’t changed, it’s when it remains at 0 we know that there has been a change to TV, AV or ISO.

That really does make it confusing and easy to see why it looks like the EV is changing. Because, well, the number next to EV is changing.

 

[With The Birds]

That really does make it confusing and easy to see why it looks like the EV is changing. Because, well, the number next to EV is changing.

Yep..... one way of looking at it might be to take it as how many stops you need to move the shutter or aperture to match the metered exposure. It’s easy to see why aperture and shutter priority modes are so handy for instances where your happy to trust the camera metering to get it right. I shoot full manual mostly (that’s all I had when I first picked up a camera) so I just got used to it. That first camera just had a needle visible in the viewfinder for the light metering which is analogous to the +/- EV numbers. It simply let you know which way you had to move your settings to get the needle centred.

I occasionally give people a hand starting out with photography and that usually involves loaning then a full manual camera and giving them a few rolls of transparency or B/W negative film. It’s a great way to get them used to the relationships between settings.

 

[bsartist]

Yep..... one way of looking at it might be to take it as how many stops you need to move the shutter or aperture to match the metered exposure. It’s easy to see why aperture and shutter priority modes are so handy for instances where your happy to trust the camera metering to get it right. I shoot full manual mostly (that’s all I had when I first picked up a camera) so I just got used to it. That first camera just had a needle visible in the viewfinder for the light metering which is analogous to the +/- EV numbers. It simply let you know which way you had to move your settings to get the needle centred.

I occasionally give people a hand starting out with photography and that usually involves loaning then a full manual camera and giving them a few rolls of transparency or B/W negative film. It’s a great way to get them used to the relationships between settings.

Ok I yeah. I started out with match needle metering on a Nikkormat FT2 then a Nikon F2 while in high school. I have no problem with the concepts. I’m just pointing out from a terminology perspective I see where the confusion that started this thread came from.

 

[With The Birds]

Ok I yeah. I started out with match needle metering on a Nikkormat FT2 then a Nikon F2 while in high school. I have no problem with the concepts. I’m just pointing out from a terminology perspective I see where the confusion that started this thread came from.

I’m agreeing with you 100%....

I wish I had gone back to the analogue light meter analogy earlier. It’s clear to me now that is almost certainly where the modern EV display evolved from. Not just the needle in the camera either- before that EV was used to translate and dial in the hand held meter readings to the camera. We still use EV as the reference for manual off camera flash also.

 

[Lindsaybev]

Hi
My name is Mario. I'm from Poland. I'm amateur pilot and hobbyist.
I have Phantom 3 Standard.
I personally do panoramas like this:
-three rows of photos (360)
-photo tabs 50%
-time such that the sun would be as high as possible

Look at my panorams (my small city - seaside town)

krpano - panorama4

Hi
My name is Mario. I'm from Poland. I'm amateur pilot and hobbyist.
I have Phantom 3 Standard.
I personally do panoramas like this:
-three rows of photos (360)
-photo tabs 50%
-time such that the sun would be as high as possible

Look at my panorams (my small city - seaside town)

krpano - panorama4

Mario! How did you do that with your video? THAT is really, REALLY neat! Please let me know! Great video, by the way. I enjoyed that thoroughly.